The last decade has seen a rapid growth in the number and use of mobile cellular telephones. More recently, wireless devices have been introduced which combine the functionality of mobile telephones and Personal Digital Assistants (PDAs). It is expected that this area will undergo massive growth in the near future as new cellular telecommunication standards (i.e. GPRS, UMTS, and WAP) make possible the high speed transfer of data across the wireless interface.
It can be expected that such platforms will be susceptible to attack from so-called “malware” such as viruses, Trojan horses, and worms (referred to collectively hereinafter as “viruses”); and other unwanted/harmful content in much the same way as present day personal computers and workstations are susceptible. A number of mobile telephone viruses have already been identified.
In order to resist virus attacks, anti-virus software must be deployed into mobile platforms in much the same way as it has been deployed in the desktop environment. A number of different desktop anti-virus applications are currently available. The majority of these applications rely upon a basic scanning engine which searches suspect files for the presence of predetermined virus signatures. These signatures are held in a database which must be constantly updated to reflect the most recently identified viruses.
Typically, users download replacement databases every so often, either over the Internet, from a received e-mail, or from a CDROM or floppy disk. Users are also expected to update there software engines every so often in order to take advantage of new virus detection techniques which may be required when a new strain of virus is detected.
Mobile wireless platforms present a series of problems for software developers (including developers of anti-virus software). In particular, mobile wireless applications are traditionally not standardized, requiring a scanner to identify information about the application prior to any scanning operation being executed. Unfortunately, this information gathering takes its toll on the performance of the scanning process.